essay on the importance of sleep

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Why a Good Night’s Sleep Is Important for Your Health

• Restoration
• Stress Reduction
• Body Weight
• Illness Prevention
• Mental Health

How to Improve Your Sleep

Sleep is important due to the impact it has on your overall health. Appropriate sleep is needed for mental focus and memory, managing stress, maintaining proper body weight, boosting the immune system, and a host of other wellness needs. Some studies suggest sleep can help to prevent illness, such as diabetes or obesity .

Adults aged 18 to 60 years should get at least seven hours of sleep each night in order to achieve the benefits of sleep. If not, you run the risk of becoming sleep-deprived .

This article explains the role of sleep in overall health and offers tips on how to improve your sleep. Research on sleep and sleep cycles has elevated awareness about sleep hygiene (healthy sleep habits) and the quality of sleep.

 Illustration by Emily Roberts for Verywell Health

Sleep Is Restorative

When you sleep, you allow your body to repair and rebuild. During this time, the body is able to clear debris from the lymphatic system, which boosts the immune system.

While you sleep, there are many important processes that happen, including:

• Muscle repair
• Protein synthesis
• Tissue growth
• Hormone release

Sleep Reduces Stress

Sleep is a powerful stress reliever. It improves concentration, regulates mood, and sharpens judgment and decision-making. A lack of sleep not only reduces mental clarity but the ability to cope with stressful situations.

This is due, in part, to changes in cortisol levels. Typically, your cortisol levels fall in the evening hours, as one element of the body’s natural preparation for sleep. When sleep is lost, cortisol levels remain high and interfere with the release of melatonin, a hormone that is essential for the regulation of sleep-wake cycles.

Some studies suggest these changes could even be used to evaluate depression in people with bipolar disorder. Other studies demonstrate a link between sleep, chronic stress, and depression with an eye on heart rate changes.

Sleep Improves Your Memory

The link between sleep and memory processing is well established. Sleep serves as an opportunity for the mind to process all the stimuli taken in while awake. It triggers changes in the brain that strengthen neural connections helping us to form memories.

Sleep quality is important when learning new information and using memory. Numerous research studies find that electrophysiological, neurochemical, and genetic mechanisms that take place during the slow-wave sleep stage of sleep are key.

Sleep Helps You Maintain a Healthy Body Weight

When you are sleep deprived, your body alters the hormones that regulate hunger and appetite. These hormones include:

• Leptin: This hormone suppresses appetite and encourages the body to expend energy.
• Ghrelin: This hormone triggers feelings of hunger.

Both of these hormones are thrown off when you are short on sleep—leptin goes down and ghrelin goes up. Obstructive sleep apnea , a serious sleep disorder, is linked with obesity as well.

Sleep and Appetite

Sleep deprivation can activate the endocannabinoid (eCB) system in the brain (the same areas activated by marijuana) which increases hunger and appetite. Stimulating the eCB reward system makes you more likely to crave junk food.  You are also more likely to make these unhealthy lifestyle choices when you are tired. If that's often the case, it can lead to weight gain or diabetes over time.  

Sleep May Prevent Illnesses

Sleep deprivation can have very detrimental health impacts and has been linked to chronic diseases such as diabetes and heart disease. Here are some of the health conditions in which it may play a role.

Respiratory Illness and Infection

Lack of sleep makes you more vulnerable to respiratory illness and infection. A study of more than 600,000 people found that insomnia was a contributing cause when catching a cold or the flu , as well as a factor in how severe the infection became.

Obstructive sleep apnea, a common sleep disturbance, is linked with a number of cardiovascular (heart and blood vessel) diseases. For example, 40% to 60% of people experiencing symptomatic heart failure also are diagnosed with sleep-disordered breathing.

Other heart conditions linked with sleep apnea include:

• Coronary artery disease
• Pulmonary hypertension
• High blood pressure
• Heart arrhythmias

There's no direct evidence to suggest that sleep quantity or quality affects the risk of cancer, although studies have looked at the role of sleep in developing breast cancer , lung cancer , and more.

For example, research on lung cancer suggests a relationship between lack of sleep and adenocarcinoma risk, but more research on sleep traits (how long you sleep, whether you take naps) is needed.

Studies also are exploring the role of sleep in those already diagnosed with cancer, especially because difficulty sleeping affects up to 95% of people receiving cancer treatment and care. Sleep deprivation may affect the body's ability to fight cancer and lead to a poor prognosis, which was the conclusion of researchers focused on liver cancer .

A number of studies have shown that sleep deprivation leads to reduced glucose tolerance and impaired insulin sensitivity in humans. Additional studies suggest the risk of type 2 diabetes rises due to inadequate sleep, with seven or eight hours considered the optimal amount.

Researchers also think the timing of sleep may have impacts, too. Disruptions in circadian rhythm, with many people working at night or otherwise "living against the clock" of natural sleep cycles, also have impacts. Sleep disruption appears to affect metabolism and related diseases.

Neurodegenerative Disease

Sleep plays a key role in how your body produces cerebrospinal fluid (CSF), what it's composed of, and how the CSF is distributed in your brain and spinal cord. A number of studies have looked at how components in CSF, like amyloid-beta levels, might be linked to Alzheimer's disease and other neurodegenerative disorders.

The research results are mixed, but there is evidence to suggest that sleep patterns affect levels of amyloid-beta, orexin, tau proteins, interleukin 8 (IL-8), and other components. This may influence the development of Lewy body dementia, Parkinson's, or Alzheimer's disease, or it may contribute to sleep disruptions that are common in people living with these disorders.

Researchers also are investigating the role of CSF, sleep, and the early development of autism .

Sleep Is Important for Your Mental Health

Evidence suggests lack of sleep contributes to the formation of new mental health problems and to the maintenance of existing ones, but the magnitude of its effect is difficult to estimate and may be different across mental health conditions.

Sleep problems are very common in those with mental illness. In fact, disrupted sleep is commonly seen as both a symptom and consequence of mental health disorders, although sleep deprivation is rarely treated as the cause of mental health conditions.

The most common sleep problem associated with poor mental health is insomnia, with symptoms of:

• Not feeling well-rested after a night's sleep
• Daytime tiredness or sleepiness
• Irritability, depression, or anxiety
• Difficulty paying attention, focusing on tasks, or remembering
• Increased errors or accidents
• Ongoing worries about sleep

You may experience insomnia for a number of reasons, but the most common culprits are: 

• Work schedule
• Poor sleep habits
• Excessive alcohol or caffeine use at night 
• Habitual nighttime screen use

Illustration by JR Bee for Verywell Health

Small changes to your nighttime routine can result in a huge health benefit:

• Establish a realistic bedtime and stick to it every night, even on the weekends.
• Maintain comfortable temperature settings and low light levels in your bedroom.
• Consider a “screen ban” on televisions, computers and tablets, cell phones, and other electronic devices in your bedroom.
• Abstain from caffeine, alcohol, and large meals in the hours leading up to bedtime.
• Refrain from using tobacco at any time of day or night.
• Exercise during the day; this can help you wind down in the evening and prepare for sleep.

Sleep is vital to maintaining health, and most adults need seven or more hours each day. There is increasing evidence that adequate, high-quality sleep can help prevent illnesses like respiratory infection as well as limit the risk of diabetes, heart disease, and other serious conditions.

Memory, mood, and mental health also are affected by sleep deprivation and other sleep disorders.

There are lifestyle steps you can take to improve sleep. Talk to your healthcare provider if you have concerns or questions about how sleep patterns are affecting your health.

Antza C, Kostopoulos G, Mostafa S, Nirantharakumar K, Tahrani A. The links between sleep duration, obesity and type 2 diabetes mellitus . J Endocrinol . 2021 Dec 13;252(2):125-141. doi:10.1530/JOE-21-0155.

Watson NF, Badr MS, Belenky G, Bliwise DL, Buxton OM, Buysse D, et al . Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society . Sleep . 2015 Jun 1;38(6):843-4. doi:10.5665/sleep.4716.

Chong PLH, Garic D, Shen MD, Lundgaard I, Schwichtenberg AJ. Sleep, cerebrospinal fluid, and the glymphatic system: A systematic review . Sleep Med Rev . 2022 Feb;61:101572. doi:10.1016/j.smrv.2021.101572. 

Walker WH 2nd, Walton JC, DeVries AC, Nelson RJ. Circadian rhythm disruption and mental health . Transl Psychiatry . 2020 Jan 23;10(1):28. doi:10.1038/s41398-020-0694-0. 

da Estrela C, McGrath J, Booij L, Gouin JP. Heart Rate Variability, Sleep Quality, and Depression in the Context of Chronic Stress . Ann Behav Med . 2021 Mar 16;55(2):155-164. doi:10.1093/abm/kaaa039.

Tucker MA, Humiston GB, Summer T, Wamsley E. Comparing the effects of sleep and rest on memory consolidation . Nature and Science of Sleep . 2020 Feb 3;12:79-91. doi:10.2147/NSS.S223917

Rasch B, Born J. About sleep’s role in memory .  Physiological Reviews . 2013;93(2):681-766. doi: 10.1152/physrev.00032.2012 

Chaput JP, McHill AW, Cox RC, Broussard JL, Dutil C, da Costa BGG, Sampasa-Kanyinga H, Wright KP Jr. The role of insufficient sleep and circadian misalignment in obesity . Nat Rev Endocrinol . 2023 Feb;19(2):82-97. doi:10.1038/s41574-022-00747-7.

Yeghiazarians Y, Jneid H, Tietjens JR, Redline S, Brown DL, El-Sherif N, et al . Obstructive Sleep Apnea and Cardiovascular Disease: A Scientific Statement From the American Heart Association . Circulation . 2021 Jul 20;144(3):e56-e67. doi:10.1161/CIR.0000000000000988.

Hanlon EC, Tasali E, Leproult R, Stuhr KL, Doncheck E, de Wit H, Hillard CJ, Van Cauter E.  Sleep restriction enhances the daily rhythm of circulating levels of endocannabinoid 2-arachidonoylglycerol . 2016 Mar 1;39(3):653-64. doi:10.5665/sleep.5546

Jones SE, Maisha FI, Strausz SJ, Lammi V, Cade BE, Tervi A, et al . The public health impact of poor sleep on severe COVID-19, influenza and upper respiratory infections . EBioMedicine . 2023 Jul;93:104630. doi:10.1016/j.ebiom.2023.104630

Wang J, Tang H, Duan Y, Yang S, An J. Association between Sleep Traits and Lung Cancer: A Mendelian Randomization Study . J Immunol Res . 2021 Jun 21;2021:1893882. doi:10.1155/2021/1893882. 

Büttner-Teleagă A, Kim YT, Osel T, Richter K. Sleep Disorders in Cancer-A Systematic Review . Int J Environ Res Public Health . 2021 Nov 7;18(21):11696. doi:10.3390/ijerph182111696.

Huang J, Song P, Hang K, Chen Z, Zhu Z, Zhang Y, et al . Sleep Deprivation Disturbs Immune Surveillance and Promotes the Progression of Hepatocellular Carcinoma . Front Immunol . 2021 Sep 3;12:727959. doi:10.3389/fimmu.2021.727959.

Parameswaran G, Ray DW. Sleep, circadian rhythms, and type 2 diabetes mellitus . Clin Endocrinol (Oxf) . 2022 Jan;96(1):12-20. doi:10.1111/cen.14607. 

Chasens ER, Imes CC, Kariuki JK, Luyster FS, Morris JL, DiNardo MM, et al . Sleep and Metabolic Syndrome . Nurs Clin North Am . 2021 Jun;56(2):203-217. doi:10.1016/j.cnur.2020.10.012.

Scott AJ, Webb TL, Rowse G. Does improving sleep lead to better mental health? A protocol for a meta-analytic review of randomised controlled trials . BMJ Open. 2017;7(9):e016873. Published 2017 Sep 18. doi:10.1136/bmjopen-2017-016873

By Shamard Charles, MD, MPH Shamard Charles, MD, MPH is a public health physician and journalist. He has held positions with major news networks like NBC reporting on health policy, public health initiatives, diversity in medicine, and new developments in health care research and medical treatments.

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MORE INFORMATION

How Sleep Works Why Is Sleep Important?

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Sleep plays a vital role in good health and well-being throughout your life. The way you feel while you are awake depends in part on what happens while you are sleeping. During sleep, your body is working to support healthy brain function and maintain your physical health.

In children and teens, sleep also helps support growth and development. Getting inadequate sleep over time can raise your risk for chronic (long-term) health problems. It can also affect how well you think, react, work, learn, and get along with others. Learn how sleep affects your heart and circulatory system, metabolism , respiratory system, and immune system and how much sleep is enough.

This brochure describes the differences between the types of sleep needed to feel awake and to be healthy and offers tips for getting a good night’s sleep.

Heart and circulatory system

When you fall asleep and enter non-REM sleep , your blood pressure and heart rate fall. During sleep, your parasympathetic system controls your body, and your heart does not work as hard as it does when you are awake. During REM sleep and when waking, your sympathetic system is activated, increasing your heart rate and blood pressure to the usual levels when you are awake and relaxed. A sharp increase in blood pressure and heart rate upon waking has been linked to angina, or chest pain, and heart attacks .

People who do not sleep enough or wake up often during the night may have a higher risk of:

• Coronary heart disease
• High blood pressure

Hormones and sleep

Your body makes different hormone at different times of day. This may be related to your sleep pattern or your circadian clocks. In the morning, your body releases hormones that promote alertness, such as cortisol, which helps you wake up. Other hormones have 24-hour patterns that vary throughout your life; for example, in children, the hormones that tell the glands to release testosterone, estrogen, and progesterone are made in pulses at night, and the pulses get bigger as puberty approaches.

Metabolism and sleep

The way your body handles fat varies according to various circadian clocks, including those in the liver, fat, and muscle. For example, the circadian clocks make sure that your liver is prepared to help digest fats at appropriate times. Your body may handle fat differently if you eat at unusual times.

Studies have shown that not getting enough quality sleep can lead to:

• Higher levels of the hormones that control hunger, including leptin and ghrelin, inside your body
• Decreased ability to respond to insulin
• Increased consumption of food, especially fatty, sweet, and salty foods
• Decreased physical activity
• Metabolic syndrome

All of these contribute to overweight and obesity .

Respiratory and immune systems

During sleep, you breathe less often and less deeply and take in less oxygen. These changes can cause problems in people who have health problems such as asthma or chronic obstructive pulmonary disease (COPD) . Asthma symptoms are usually worse during early morning sleep. Likewise, breathing problems in people who have lung diseases such as COPD can become worse during sleep.

Sleep also affects different parts of your immune system, which become more active at different times of day. For example, when you sleep, a particular type of immune cell works harder. That is why people who do not sleep enough may be more likely to get colds and other infections.

Lung Health Basics: Sleep

People with lung disease often have  trouble sleeping. Sleep is critical to overall health, so take the first step to sleeping better: learn these sleep terms, and find out about treatments that can help with sleep apnea.

Problems with thinking and memory

Sleep helps with learning and the formation of long-term memories. Not getting enough sleep or enough high-quality sleep can lead to problems focusing on tasks and thinking clearly. Read our Sleep Deprivation and Deficiency page for more information on how lack of sleep affects performance of daily activities, including driving and schoolwork.

• Why Sleep Matters: Benefits of Sleep
• Why Sleep Matters: Consequences of Sleep Deficiency
• Why Sleep Matters: Historical and Cultural Perspectives of Sleep
• Science of Sleep: What is Sleep?
• Science of Sleep: How is Sleep Regulated?
• Genetics, Aging and Sleep: Sleep and Aging
• Genetics, Aging and Sleep: Profiles of Changes with Age
• Genetics, Aging and Sleep: the Genetics of Sleep
• Getting the Sleep You Need: Overcoming Factors that Interfere with Sleep
• Getting the Sleep You Need: You and Your Biological Clock
• Getting the Sleep You Need: Jet Lag and Shift Work
• Getting the Sleep You Need: When to Seek Treatment

The Takeaway

• When we miss sleep in order to keep up with our 24/7 world, we pay a price with our ability to learn, our health and safety, and our quality of life
• It may seem obvious that sleep is beneficial. Even without fully grasping what sleep does for us, we know that going without sleep for too long makes us feel terrible, and that getting a good night's sleep can make us feel ready to take on the world. Scientists have gone to great lengths to fully understand sleep's benefits. In studies of humans and other animals, they have discovered that sleep plays a critical role in immune function, metabolism, memory, learning, and other vital functions. 

Sleep researchers are discovering how sleep is vital for learning and memory, and how lack of sleep impacts our health, safety, and longevity.

Why Do We Sleep Anyway?

• Our bodies regulate sleep in much the same way that they regulate eating, drinking, and breathing. This suggests that sleep serves a similar critical role in our health and well-being.
• Although it is difficult to answer the question, "Why do we sleep?" scientists have developed several theories that together may help explain why we spend a third of our lives sleeping.
• Understanding these theories can help deepen our appreciation of the function of sleep in our lives.

Hunger and Eating, Sleepiness and Sleep

While we may not often think about why we sleep, most of us acknowledge at some level that sleep makes us feel better. We feel more alert, more energetic, happier, and better able to function following a good night of sleep. However, the fact that sleep makes us feel better and that going without sleep makes us feel worse only begins to explain why sleep might be necessary. One way to think about the function of sleep is to compare it to another of our life-sustaining activities: eating. Hunger is a protective mechanism that has evolved to ensure that we consume the nutrients our bodies require to grow, repair tissues, and function properly. And although it is relatively easy to grasp the role that eating serves— given that it involves physically consuming the substances our bodies need—eating and sleeping are not as different as they might seem.

Both eating and sleeping are regulated by powerful internal drives. Going without food produces the uncomfortable sensation of hunger, while going without sleep makes us feel overwhelmingly sleepy. And just as eating relieves hunger and ensures that we obtain the nutrients we need, sleeping relieves sleepiness and ensures that we obtain the sleep we need. Still, the question remains: Why do we need sleep at all? Is there a single primary function of sleep, or does sleep serve many functions?

An Unanswerable Question?

Scientists have explored the question of why we sleep from many different angles. They have examined, for example, what happens when humans or other animals are deprived of sleep. In other studies, they have looked at sleep patterns in a variety of organisms to see if similarities or differences among species might reveal something about sleep's functions. Yet, despite decades of research and many discoveries about other aspects of sleep, the question of why we sleep has been difficult to answer.

The lack of a clear answer to this challenging question does not mean that this research has been a waste of time. In fact, we now know much more about the function of sleep, and scientists have developed several promising theories to explain why we sleep. In light of the evidence they have gathered, it seems likely that no single theory will ever be proven correct. Instead, we may find that sleep is explained by two or more of these explanations. The hope is that by better understanding why we sleep, we will learn to respect sleep's functions more and enjoy the health benefits it affords. This essay outlines several current theories of why we sleep. To learn more about them, be sure to check out the References at the end of this essay. There you'll find links to articles by researchers who are studying this fascinating question.

Theories of Why We Sleep

Inactivity Theory

One of the earliest theories of sleep, sometimes called the adaptive or evolutionary theory, suggests that inactivity at night is an adaptation that served a survival function by keeping organisms out of harm’s way at times when they would be particularly vulnerable. The theory suggests that animals that were able to stay still and quiet during these periods of vulnerability had an advantage over other animals that remained active. These animals did not have accidents during activities in the dark, for example, and were not killed by predators. Through natural selection, this behavioral strategy presumably evolved to become what we now recognize as sleep. A simple counter-argument to this theory is that it is always safer to remain conscious in order to be able to react to an emergency (even if lying still in the dark at night). Thus, there does not seem to be any advantage of being unconscious and asleep if safety is paramount.

Energy Conservation Theory

Although it may be less apparent to people living in societies in which food sources are plentiful, one of the strongest factors in natural selection is competition for and effective utilization of energy resources. The energy conservation theory suggests that the primary function of sleep is to reduce an individual’s energy demand and expenditure during part of the day or night, especially at times when it is least efficient to search for food.

Research has shown that energy metabolism is significantly reduced during sleep (by as much as 10 percent in humans and even more in other species). For example, both body temperature and caloric demand decrease during sleep, as compared to wakefulness. Such evidence supports the proposition that one of the primary functions of sleep is to help organisms conserve their energy resources. Many scientists consider this theory to be related to, and part of, the inactivity theory.

Restorative Theories

Another explanation for why we sleep is based on the long-held belief that sleep in some way serves to "restore" what is lost in the body while we are awake. Sleep provides an opportunity for the body to repair and rejuvenate itself. In recent years, these ideas have gained support from empirical evidence collected in human and animal studies. The most striking of these is that animals deprived entirely of sleep lose all immune function and die in just a matter of weeks. This is further supported by findings that many of the major restorative functions in the body like muscle growth, tissue repair, protein synthesis, and  growth hormone  release occur mostly, or in some cases only, during sleep. Other rejuvenating aspects of sleep are specific to the brain and  cognitive function . For example, while we are awake, neurons in the brain produce  adenosine , a by-product of the cells' activities. The build-up of adenosine in the brain is thought to be one factor that leads to our perception of being tired. (Incidentally, this feeling is counteracted by the use of  caffeine , which blocks the actions of adenosine in the brain and keeps us alert.) Scientists think that this build-up of adenosine during wakefulness may promote the "drive to sleep." As long as we are awake, adenosine accumulates and remains high. During sleep, the body has a chance to clear adenosine from the system, and, as a result, we feel more alert when we wake. Consistent with the need to remove buildup of chemicals in the brain are recent studies in experimental animals demonstrating a previously unknown drainage pathway in the brain now known as the glymphatic system. This network of "tunnels" surrounding existing blood vessels promotes the clearance of substances from the brain. Its efficiency is enhanced during sleep; studies have shown that elimination of toxins via this pathway such as beta amyloid, a protein associated with Alzheimer's Disease is reduced with sleep deprivation.

Synaptic Homeostasis Theory

A more recent theory is that sleep is necessary to reduce neural connections or synapses in the brain. It proposes that during the day, there is an increase in the number of synapses as a result of daily activity. If allowed to continuously accumulate, the brain would become overloaded similar to a hard drive on a computer approaching its capacity. Therefore, it is necessary to prune unnecessary synapses and strengthen essential ones. Supporting this theory are studies showing that there is shrinking and expansion of synapses with sleep and wakefulness in experimental animals.

Brain Plasticity Theory

One of the most recent and compelling explanations for why we sleep is based on findings that sleep is correlated to changes in the structure and organization of the brain. This phenomenon, known as brain plasticity, is not entirely understood, but its connection to sleep has several critical implications. It is becoming clear, for example, that sleep plays a critical role in brain development in infants and young children. Infants spend about 13 to 14 hours per day sleeping, and about half of that time is spent in REM sleep, the stage in which most dreams occur. A link between sleep and brain plasticity is becoming clear in adults as well. This is seen in the effect that sleep and sleep deprivation have on people's ability to learn and perform a variety of tasks.

• Jessen NA, Munk AS, Lundgaard I, Nedergaard M. The Glymphatic System: A Beginner's Guide. Neurochem Res. 2015;40(12):2583-99. doi: 10.1007/s11064-015-1581-6.
• Porkka-Heiskanen T. Adenosine in sleep and wakefulness. Ann Med. 1999;31(2):125-9. doi: 10.3109/07853899908998788.
• Siegel JM. 2005. Clues to the functions of mammalian sleep. Nature. 437:1264-1271.
• Tononi G, Cirelli C. Sleep function and synaptic homeostasis. Sleep Med Rev. 2006;10(1):49-62. doi: 10.1016/j.smrv.2005.05.002.

Sleep, Learning and Memory

• Research suggests that sleep plays an important role in memory, both before and after learning a new task.
• Lack of adequate sleep affects mood, motivation, judgment, and our perception of events.
• Although there are some open questions about the specific role of sleep in forming and storing memories, the general consensus is that consolidated sleep throughout a whole night is optimal for learning and memory.

The Learning Process and Sleep

Sleep, learning, and memory are complex phenomena that are not entirely understood. However, animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Research suggests that sleep helps learning and memory in two distinct ways. First, a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently. Second, sleep itself has a role in the consolidation of memory, which is essential for learning new information. Although the exact mechanisms are not known, learning and memory are often described in terms of three functions.  Acquisition  refers to the introduction of new information into the brain.  Consolidation  represents the processes by which a memory becomes stable.  Recall  refers to the ability to access the information (whether consciously or unconsciously) after it has been stored. Each of these steps is necessary for proper memory function. Acquisition and recall occur only during wakefulness, but research suggests that memory consolidation takes place during sleep through the strengthening of the neural connections that form our memories. Although there is no consensus about how sleep makes this process possible, many researchers think that specific characteristics of  brainwaves  during different stages of sleep are associated with the formation of particular types of memory.

Dr. Robert Stickgold discusses how sleep plays a role in memory, both before and after a new learning situation.

Sleep researchers study the role of sleep in learning and memory formation in two ways. The first approach looks at the different stages of sleep (and changes in their duration) in response to learning a variety of new tasks. The second approach examines how sleep deprivation affects learning. Sleep deprivation can be total (no sleep allowed), partial (either early or late sleep is deprived), or selective (specific stages of sleep are deprived).

Sleep Stages and Types of Memory

Different types of memories are formed in new learning situations. Scientists are exploring whether there is a relationship between the consolidation of different types of memories and the various stages of sleep.

The earliest sleep and memory research focused on  declarative memory , which is the knowledge of fact-based information, or "what" we know (for example, the capital of France, or what you had for dinner last night). In one research study, individuals engaged in an intensive language course were observed to have an increase in  rapid-eye-movement  sleep, or REM sleep . This is a stage of sleep in which dreaming occurs most frequently. Scientists hypothesized that REM sleep played an essential role in the acquisition of learned material. Further studies have suggested that REM sleep seems to be involved in declarative memory processes if the information is complex and emotionally charged, but probably not if the information is simple and emotionally neutral. Researchers now hypothesize that  slow-wave sleep (SWS) , which is deep, restorative sleep, also plays a significant role in declarative memory by processing and consolidating newly acquired information. Studies of the connection between sleep and declarative memory have had mixed results, and this is an area of continued research.

Research has also focused on sleep and its role in  procedural memory —the remembering "how" to do something (for example, riding a bicycle or playing the piano). REM sleep seems to plays a critical role in the consolidation of procedural memory. Other aspects of sleep also play a role: motor learning seems to depend on the amount of lighter stages of sleep, while certain types of visual learning seem to depend on the amount and timing of both deep, slow-wave sleep (SWS) and REM sleep.

The Impact of Sleep Deprivation on Learning and Performance

Dr. Robert Stickgold describes studies that show the importance of sleep in memory consolidation after learning a new task.

Open Questions

Although current research suggests that sleep is essential for proper memory function, there are unanswered questions, as in any area of active scientific inquiry. For example, certain medications will significantly, if not entirely, suppress REM sleep. However, patients taking these medications do not report any memory impairment. Similarly, injuries or disease causing lesions to the  brainstem  (and subsequently eliminating a person’s REM sleep) have not resulted in any obvious loss of the ability to form new memories. Exploration and debate continue.

Not all researchers are convinced that sleep plays as prominent a role in memory consolidation as others believe. In experiments in which animals completed a course through a complicated maze, the animals' amount of REM sleep increased after performing the task. Some researchers believe that the increase in REM sleep reflects an increased demand on the brain processes that are involved in learning a new task. Other researchers, however, have suggested that any changes in the amount of REM sleep are due to the stress of the task itself, rather than a functional relationship to learning. Researchers are likewise split with regard to the impact of sleep deprivation on learning and memory. For example, rats often perform much worse on learning tasks after being selectively deprived of REM sleep. This suggests that REM sleep is necessary for the animals’ ability to consolidate the memory of how to perform the task. Some scientists have argued that the observed differences in learning are not actually due to the lack of REM sleep, but may be due to the animals not being as well rested because they were deprived a portion of their sleep.

In the view of many researchers, evidence suggests that various sleep stages are involved in the consolidation of different types of memories and that being sleep deprived reduces one’s ability to learn. Although open questions (and debate) remain, the overall evidence suggests that adequate sleep each day is very important for learning and memory.

• Ellenbogen JM, Payne JD, Stickgold R. The role of sleep in declarative memory consolidation: passive, permissive, active or none? Curr Opin Neurobiol. 2006 Dec;16(6):716-22. doi: 10.1016/j.conb.2006.

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Good Sleep for Good Health

Get the Rest You Need

Sometimes, the pace of modern life barely gives you time to stop and rest. It can make getting a good night’s sleep on a regular basis seem like a dream.

But sleep is as important for good health as diet and exercise. Good sleep improves your brain performance, mood, and health.

Not getting enough quality sleep regularly raises the risk of many diseases and disorders. These range from heart disease and stroke to obesity and dementia.

There’s more to good sleep than just the hours spent in bed, says Dr. Marishka Brown, a sleep expert at NIH. “Healthy sleep encompasses three major things,” she explains. “One is how much sleep you get. Another is sleep quality—that you get uninterrupted and refreshing sleep. The last is a consistent sleep schedule.”

People who work the night shift or irregular schedules may find getting quality sleep extra challenging. And times of great stress—like the current pandemic—can disrupt our normal sleep routines. But there are many things you can do to improve your sleep.

Sleep for Repair

Why do we need to sleep? People often think that sleep is just “down time,” when a tired brain gets to rest, says Dr. Maiken Nedergaard, who studies sleep at the University of Rochester.

“But that’s wrong,” she says. While you sleep, your brain is working. For example, sleep helps prepare your brain to learn, remember, and create.

Nedergaard and her colleagues discovered that the brain has a drainage system that removes toxins during sleep.

“When we sleep, the brain totally changes function,” she explains. “It becomes almost like a kidney, removing waste from the system.”

Her team found in mice that the drainage system removes some of the proteins linked with Alzheimer’s disease. These toxins were removed twice as fast from the brain during sleep.

Everything from blood vessels to the immune system The system that protects your body from invading viruses, bacteria, and other microscopic threats. uses sleep as a time for repair, says Dr. Kenneth Wright, Jr., a sleep researcher at the University of Colorado.

“There are certain repair processes that occur in the body mostly, or most effectively, during sleep,” he explains. “If you don’t get enough sleep, those processes are going to be disturbed.”

Sleep Myths and Truths

How much sleep you need changes with age. Experts recommend school-age children get at least nine hours a night and teens get between eight and 10. Most adults need at least seven hours or more of sleep each night.

There are many misunderstandings about sleep. One is that adults need less sleep as they get older. This isn’t true. Older adults still need the same amount. But sleep quality can get worse as you age. Older adults are also more likely to take medications that interfere with sleep.

Another sleep myth is that you can “catch up” on your days off. Researchers are finding that this largely isn’t the case.

“If you have one bad night’s sleep and take a nap, or sleep longer the next night, that can benefit you,” says Wright. “But if you have a week’s worth of getting too little sleep, the weekend isn’t sufficient for you to catch up. That’s not a healthy behavior.”

In a recent study, Wright and his team looked at people with consistently deficient sleep. They compared them to sleep-deprived people who got to sleep in on the weekend.

Both groups of people gained weight with lack of sleep. Their bodies’ ability to control blood sugar levels also got worse. The weekend catch-up sleep didn’t help.

On the flip side, more sleep isn’t always better, says Brown. For adults, “if you’re sleeping more than nine hours a night and you still don’t feel refreshed, there may be some underlying medical issue,” she explains.

Sleep Disorders

Some people have conditions that prevent them from getting enough quality sleep, no matter how hard they try. These problems are called sleep disorders.

The most common sleep disorder is insomnia. “Insomnia is when you have repeated difficulty getting to sleep and/or staying asleep,” says Brown. This happens despite having the time to sleep and a proper sleep environment. It can make you feel tired or unrested during the day.

Insomnia can be short-term, where people struggle to sleep for a few weeks or months. “Quite a few more people have been experiencing this during the pandemic,” Brown says. Long-term insomnia lasts for three months or longer.

Sleep apnea is another common sleep disorder. In sleep apnea, the upper airway becomes blocked during sleep. This reduces or stops airflow, which wakes people up during the night. The condition can be dangerous. If untreated, it may lead to other health problems.

If you regularly have problems sleeping, talk with your health care provider. They may have you keep a sleep diary to track your sleep for several weeks. They can also run tests, including sleep studies. These look for sleep disorders.

Getting Better Sleep

If you’re having trouble sleeping, hearing how important it is may be frustrating. But simple things can improve your odds of a good night’s sleep. See the Wise Choices box for tips to sleep better every day.

Treatments are available for many common sleep disorders. Cognitive behavioral therapy can help many people with insomnia get better sleep. Medications can also help some people.

Many people with sleep apnea benefit from using a device called a CPAP machine. These machines keep the airway open so that you can breathe. Other treatments can include special mouthguards and lifestyle changes.

For everyone, “as best you can, try to make sleep a priority,” Brown says. “Sleep is not a throwaway thing—it’s a biological necessity.”

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Sleep 101: Why Sleep Is So Important to Your Health

Erica Jansen

Research assistant professor of nutritional sciences.

March 2, 2020

What is sleep exactly, and how does it help us stay healthy?

Sleep is an altered state of consciousness where we have limited interactions with our surroundings and are relatively quiet and still (depending on the stage of sleep). Contrary to our quiet physical state, the brain is very active during sleep, carrying out many important functions. Sleep is essential to every process in the body, affecting our physical and mental functioning the next day, our ability to fight disease and develop immunity, and our metabolism and chronic disease risk. Sleep is truly interdisciplinary because it touches every aspect of health.

Sleep is essential to every process in the body, affecting our physical and mental functioning the next day, our ability to fight disease and develop immunity, and our metabolism and chronic disease risk.

How does what we eat impact our sleep?

It is well-known that certain substances, such as caffeine, can affect the onset of sleep in a negative way. On the other hand, evidence is growing that shows how other foods like tart cherries, kiwi, fatty fish (like salmon and tuna), and malted milk may have beneficial effects on sleep. More recently, studies have shown that healthy dietary patterns overall—not just specific foods—could be associated with longer sleep duration and shorter time to fall asleep.

Why is sleep so important for young children, and what are some of the common negative effects of poor sleep?

Sleep is important for every part of the body, and it is especially important for young children as their bodies and minds develop. In young children, lack of sleep or poor quality sleep can be associated with difficult behaviors, lower capacity to learn and retain information, and a propensity for poor eating patterns and weight gain.

What sleep needs do adolescents have, and what does this mean for the current conversations we're having around school-day start times?

Adolescents need around 8-10 hours of sleep per night, but a high proportion do not get that amount. For example, recent estimates suggest that 60 percent of middle schoolers and 70 percent of high schoolers don’t get adequate sleep on school nights. This figure is even higher for Michigan high schoolers, which is at 80 percent. One of the main reasons adolescents are so sleep-deprived is that biological changes in their brain affect when they feel sleepy. So even if they are sleep-deprived, they often can’t go to bed early because their brain is not yet prepared to sleep.

In school districts that have enacted later school start times, research is consistently showing that students get more sleep and as a result have fewer motor vehicle accidents, better grades, and improved mental health.

The problem with these delayed bedtimes is that school or before-school activities often start very early, so adolescents may end up chronically sleep deprived. In school districts that have enacted later school start times, research is consistently showing that students get more sleep and as a result have fewer motor vehicle accidents, better grades, and improved mental health.

Every spring and fall we change our clocks by an hour. What health impacts does this change have on individuals and on the public’s health?

There are many calls from the sleep-research community to eliminate daylight savings time. When our clocks are pushed forward, people lose one hour of sleep. This one-hour sleep loss is associated with significantly more motor vehicle accidents as well as cardiac events. When our clocks move backward, we might think that extra hour helps us. But our sleep patterns are disrupted by any change like this, so the fall time change may also lead to negative health impacts. In general, these universal time changes create a significant and negative burden on the public’s health.

How important is sleep for our mental health?

Sleep and mental health go hand-in-hand. Good sleep is essential for maintaining our baseline mental health, as one night of sleep deprivation can dramatically affect mood the next day. Chronic exposure to poor sleep quality is associated with depression, anxiety, and other conditions. There are also bidirectional associations—meaning that experiencing anxiety and depression very often affects sleep, which then impacts our ability to cope with the anxiety and depression, and so on.

How does alcohol impact sleep?

Although alcohol may help a person fall asleep quickly, it hinders sleep quality, often causing fragmented (interrupted) sleep. When consuming alcohol, it is recommended to do so several hours before bedtime so that the alcohol is completely out of the system before sleep.

Does screen time really affect our sleep?

There is evidence to show that screen use right before bed could impact sleep. One reason is that the blue light emitted from these devices can affect the secretion of melatonin, the hormone that helps signal to the body that it is time to fall asleep. Other reasons include the content of what is on the screen. If you watch a scary movie, read an emotionally-driven article, or consume any other anxiety-producing content on your screen, it can affect your ability to fall asleep. Sleep clinicians recommend putting away all screens at least one hour before bed and to instead do some light reading or other relaxing activity.

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Why sleep is essential for health

Sleep is important for maintaining optimal health and well-being. Like exercise and a balanced diet, getting enough sleep may help prevent a range of health issues, including heart disease and depression.

Modern-day living in the United States and many other countries does not always embrace the necessity for adequate sleep. Yet, it is important that people make an effort to get enough sleep regularly.

The following are some of the many benefits health professionals associate with getting a good night’s rest.

1. Better memory and performance

A 2017 study looked into the short and long-term health consequences of sleep disruption.

Researchers noted that sleep has links to several brain functions, including:

• Memory: Sleep disruption may affect memory processing and formation.
• Performance : People’s performance at work, school, and other settings is affected by sleep disruption. This includes focus, emotional reactivity, decision-making, risk-taking behavior, and judgment.
• Cognition: By affecting stress hormones, sleep disruption may affect cognition.

A 2015 study in the Journal of Child Psychology and Psychiatry showed that children’s sleep patterns could directly impact their behavior and academic performance.

2. Lower weight gain risk

The link between weight gain and obesity and short sleep patterns is unclear.

There have been several studies throughout the years that have linked obesity and poor sleep patterns.

A 2018 study suggests that people who regularly sleep less than seven hours a night are more likely to have a higher body mass index (BMI) and develop obesity than those who sleep more.

Researchers suggested sleep deprivation is associated with higher levels of gherlin (the hunger hormone), salt retention and inflammatory markers. They also noted that decreased sleep results in increased fatigue, which may affect a person’s desire or ability to exercise and maintain a healthful lifestyle.

More research is needed to better understand the links between poor sleep and weight gain.

Resources for healthy sleep

To discover more evidence-based information and resources on the science of healthy sleep, visit our dedicated hub .

3. Better calorie regulation

Similarly to gaining weight, there is evidence to suggest that getting a good night’s sleep can help a person’s body take in fewer calories .

For example, a 2022 clinical trial found that overweight adults who increased their sleep duration took in fewer calories compared with a control group.

The adults increased their sleep by 1.2 hours on average, and took in around 270 calories fewer than the control group. The researchers suggested that improving and maintaining healthy sleep duration could help with weight loss and obesity prevention.

4. Greater athletic performance

Adults need between 7 and 9 hours of sleep a night, but recent studies have suggested that athletes may need more.

Sleep is important for athletes and people participating in sport because the body heals during sleep. Other benefits include:

• better endurance
• more energy
• better accuracy and reaction time
• faster speed
• better mental functioning

5. Lower risk of heart disease

One risk factor for heart disease is high blood pressure . According to the Centers for Disease Control and Prevention (CDC) , getting adequate rest each night allows the body’s blood pressure to regulate itself.

Getting a good night’s sleep can also reduce the chances of sleep-related conditions such as apnea and promote better overall heart health.

6. More emotional and social intelligence

Sleep has links to people’s emotional and social intelligence. Someone who does not get adequate sleep is more likely to have issues with recognizing other people’s emotions and expressions.

For example, a 2022 study looked into the relationship between sleep quality and duration and emotional intelligence.

477 participants were asked to complete questionnaires about sleep habits and emotional intelligence. People who routinely experienced higher quality sleep tended to perceive themselves as having better emotional intelligence, such as doing well in social interactions, maintaining relationships, feeling positive and controlling impulses.

7. Preventing depression

The association between sleep and mental health has been the subject of research for a long time. A 2016 meta-analysis concluded that insomnia is significantly associated with an increased risk of depression.

The review suggests that sleep loss may result in cognitive alterations that lead to depression risk.

Sleep disturbance may also impair emotional regulation and stability, as well as altering neural processes, which may all lead to symptoms of depression.

8. Lower inflammation

There is a link between getting adequate sleep and reducing inflammation in the body.

For example, a 2019 study found a significant positive association between greater sleep inconsistency and higher levels of inflammation, particularly in women.

The study suggested that inconsistent sleep, where a person goes to bed at inconsistent times or wakes up at different times each night, can disturb the body’s process of regulating inflammation during sleep.

9. Stronger immune system

Sleep helps the body repair, regenerate, and recover. The immune system is no exception to this relationship. Some research suggests that deep sleep is neccessary for the body to repair itself and strengthen the immune system.

However, scientists still need to do further research into the exact mechanisms of sleep in regards to its impact on the body’s immune system.

Stages of sleep

When people sleep, their body goes through four stages of sleep.

Three of these stages are non-rapid eye movement (NREM) sleep, with each stage a progressively deeper sleep. The final stage is rapid eye movement (REM) sleep, where dreaming mostly occurs.

The body cycles through each stage around four to six times over the course of a night.

Read on to find out more about each stage of sleep.

Stage 1 NREM (Light sleep)

This is the lightest stage of NREM sleep, where a person transitions from wakefulness to sleep.

In this stage, a person’s brain waves, heartbeat, breathing, and eye movements slow. Their muscles also relax, with occasional twitching.

A person usually spends only 5% of their total sleep time in stage 1, which typically lasts several minutes at a time.

Stage 2 NREM (Deeper sleep)

In this stage, a person’s heart rate slows and muscles relax further. Their body temperature drops and eye movements stop.

A person’s brain-wave activity slows but they experience brief bursts of electrical activity, known as sleep spindles. Studies suggest sleep spindles help with memory consolidation.

People spend most of their total sleep time in stage 2 (about 45%). This stage typically lasts around 25 minutes in the first cycle, with time increasing in each cycle.

Stage 3 NREM (Deepest sleep)

This is the deepest stage of sleep, also known as slow-wave sleep (SWS), and accounts for about 25% of total sleep time.

A person’s heart rate, breathing, and brain waves slow to their lowest levels, and muscles completely relax. This stage is the hardest to awaken from, and when sleepwalking, bedwetting, and night terrors occur.

In this stage, a person’s body repairs itself, regrows tissues, strengthens the immune system, and builds bone and muscle. A person needs this stage of sleep to wake up feeling refreshed.

Stage 4 REM (Dreaming)

This is the stage of sleep where dreaming and nightmares mostly occur. It usually begins about 90 minutes after a person falls asleep.

A person’s eyes move rapidly from side to side with eyelids closed during this stage, and heart rate and breathing increase.

Brain activity becomes closer to that seen in wakefulness, but arm and leg muscles become paralyzed to stop a person from acting out their dreams. Experts believe a person needs some REM and non-REM sleep for memory consolidation.

People spend around 25% of total sleep time in REM sleep, with each cycle lasting from 10 minutes to an hour.

Learn more about sleep stages here.

How much sleep do we need?

Sleep needs vary from person to person, depending on their age. As a person ages, they typically require less sleep to function properly.

According to the CDC , the breakdown is as follows:

• Newborns (0–3 months): 14–17 hours
• Infants (4–12 months): 12–16 hours
• Toddler (1–2 years): 11–14 hours
• Preschool (3–5 years): 10–13 hours
• School age (6–12 years): 9–12 hours
• Teen (13–18 years): 8–10 hours
• Adult (18–60 years): 7-plus hours
• Adult (61–64 years): 7–9 hours
• Adult (65+ years): 7–8 hours

As well as the number of hours, the quality of sleep is also important. Signs of poor sleep quality include:

• Waking in the middle of the night.
• Still not feeling rested after an adequate number of hours sleep.

Tips for improving sleep

Some things a person can do to improve sleep quality are:

• Avoiding sleeping in when you have had enough sleep.
• Going to bed around the same time each night.
• Spending more time outside and being more active during the day.
• Reducing stress through exercise, therapy, or other means.

Learn more about how to sleep better.

Sleep is a vital, often neglected, component of every person’s overall health and well-being. Sleep is important because it enables the body to repair and be fit and ready for another day.

Getting adequate rest may also help prevent excess weight gain, heart disease, and increased illness duration.

Read the article in Spanish.

• Brain basics: Understanding sleep. (2022). https://www.ninds.nih.gov/health-information/patient-caregiver-education/brain-basics-understanding-sleep
• Cooper, C. B., et al . (2018). Sleep deprivation and obesity in adults: a brief narrative review. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6196958/
• Dzierzewski, J. M., et al . (2020). Sleep Inconsistency and Markers of Inflammation. https://www.frontiersin.org/articles/10.3389/fneur.2020.01042/full
• Fernandez, L. M. J., et al . (2020). Sleep Spindles: Mechanisms and Functions. https://journals.physiology.org/doi/full/10.1152/physrev.00042.2018
• Hayley, A. C., et al. (2015). The relationships between insomnia, sleep apnoea and depression: Findings from the American National Health and Nutrition Examination Survey, 2005–2008. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/25128225/
• How does sleep affect your heart health? (2021). https://www.cdc.gov/bloodpressure/sleep.htm
• How much sleep do I need? (2017). https://www.cdc.gov/sleep/about_sleep/how_much_sleep.html
• Kilgore, W. D. S., et al . (2022). Sleep quality and duration are associated with greater trait emotional intelligence. https://www.sciencedirect.com/science/article/pii/S2352721821001534
• Könen, T., et al. (2015). Cognitive benefits of last night’s sleep: Daily variations in children’s sleep behavior are related to working memory fluctuations. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/25052368/
• Li, L., (2016). Insomnia and the risk of depression: a meta-analysis of prospective cohort studies. https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-016-1075-3
• Patel, A. K., et al . (2022). Physiology, Sleep Stages. https://www.ncbi.nlm.nih.gov/books/NBK526132/
• Tasali, E., et al . (2022). Effect of Sleep Extension on Objectively Assessed Energy Intake Among Adults With Overweight in Real-life Settings: A Randomized Clinical Trial. https://pubmed.ncbi.nlm.nih.gov/35129580/
• Walsh, N. P., et al . (2021). Sleep and the athlete: narrative review and 2021 expert consensus recommendations. https://bjsm.bmj.com/content/55/7/356
• Watson, A. (2017). Sleep and Athletic Performance. https://journals.lww.com/acsm-csmr/fulltext/2017/11000/sleep_and_athletic_performance.11.aspx

Last medically reviewed on August 16, 2022

• Heart Disease
• Anxiety / Stress
• Obesity / Weight Loss / Fitness
• Sleep / Sleep Disorders / Insomnia

How we reviewed this article:

• Ali, T., et al. (2013). Sleep, immunity and inflammation in gastrointestinal disorders. https://www.ncbi.nlm.nih.gov/pubmed/24409051
• Bernert, R. A., et al. (2014). Association of poor subjective sleep quality with risk for death by suicide during a 10-year period: A longitudinal, population-based study of late life. https://www.ncbi.nlm.nih.gov/pubmed/25133759
• Besedovsky, L., et al. (2012). Sleep and immune function. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3256323/
• Di Milia, L., et al. (2013). The association between short sleep and obesity after controlling for demographic, lifestyle, work and health related factors. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/23419528/
• Guadagni, V., et al. (2014). The effects of sleep deprivation on emotional empathy. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/25117004/
• Hayley, A. C., et al. (2015). The relationships between insomnia, sleep apnoea and depression: Findings from the American National Health and Nutrition Examination Survey, 2005–2008. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/25128225/
• How does sleep affect your heart health? (2018). https://www.cdc.gov/features/sleep-heart-health/index.html
• How sleep affects athletes’ performance. (n.d.). https://www.sleep.org/articles/how-sleep-affects-athletes/
• Könen, T., et al. (2015). Cognitive benefits of last night's sleep: Daily variations in children's sleep behavior are related to working memory fluctuations. [Abstract]. https://www.ncbi.nlm.nih.gov/pubmed/25052368/
• Markwald, R. R., et al. (2013). Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3619301/

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Why You Should Make a Good Night’s Sleep a Priority

Poor sleep habits and sleep deprivation are serious problems for most high school and college students. This guide offers important tips on how—and why—to improve your sleep hygiene.

The time you spend in high school and college can be both fun and rewarding. At the same time, these can be some of the busiest years of your life.

Balancing all the demands on your time—a full course load, extracurricular activities, and socializing with friends—can be challenging. And if you also work or have family commitments, it can feel like there just aren’t enough hours in the day. 

With so many competing priorities, sacrificing sleep may feel like the only way to get everything done. 

Despite the sleepiness you might feel the next day, one late night probably won’t have a major impact on your well-being. But regularly short-changing yourself on quality sleep can have serious implications for school, work, and your physical and mental health.

Alternatively, prioritizing a regular sleep schedule can make these years healthier, less stressful, and more successful long-term.

The sleep you need versus the sleep you get

According to the National Sleep Foundation , high school students (ages 14-17) need about eight to 10 hours of sleep each night. For young adults (ages 18 to 25), the range is need between seven and nine hours.

How do you know how much sleep you need within this range? 

According to Dr. Edward Pace-Schott, Harvard Summer School and Harvard Medical School faculty member and sleep expert, you can answer that question simply by observing how much you sleep when you don’t need to get up.

“When you’ve been on vacation for two weeks, how are you sleeping during that second week? How long are you sleeping? If you’re sleeping eight or nine hours when you don’t have any reason to get up, then chances are you need that amount or close to that amount of sleep,” says Pace-Schott. 

Most students, however, get far less sleep than the recommended amount. 

Seventy to 96 percent of college students get less than eight hours of sleep each week night. And over half of college students sleep less than seven hours per night. The numbers are similar for high school students; 73 percent of high school students get between seven and seven and a half hours of sleep .

Of course, many students attempt to catch up on lost sleep by sleeping late on the weekends. Unfortunately, this pattern is neither healthy nor a true long-term solution to sleep deprivation. 

And what about those students who say that they function perfectly well on just a couple hours of sleep?

“There are very few individuals who are so-called short sleepers, people who really don’t need more than six hours of sleep. But, there are a lot more people who claim to be short sleepers than there are real short sleepers,” says Pace-Schott.

Consequences of sleep deprivation

The consequences of sleep deprivation are fairly well established but may still be surprising.

For example, did you know that sleep deprivation can create the same level of cognitive impairment as drinking alcohol? 

According to the CDC , staying awake for 18 hours can have the same effect as a blood alcohol content (BAC) of 0.05 percent. Staying awake for 24 hours can equate to a BAC of 0.10 percent (higher than the legal limit of 0.08 percent). 

And according to research by AAA , drowsy driving causes an average of 328,000 motor vehicle accidents each year in the US. Drivers who sleep less than five hours per night are more than five times as likely to have a crash as drivers who sleep for seven hours or more.  

Other signs of chronic sleep deprivation include:

• Daytime sleepiness and fatigue
• Irritability and short temper
• Mood changes
• Trouble coping with stress
• Difficulty focusing, concentrating, and remembering

Over the long term, chronic sleep deprivation can have a serious impact on your physical and mental health. Insufficient sleep has been linked, for example, to weight gain and obesity, cardiovascular disease, and type 2 diabetes.

The impact on your mental health can be just as serious. Harvard Medical School has conducted numerous studies, including research by Pace-Schott, demonstrating a link between sleep deprivation and mental health disorders such as anxiety and depression.

Earn college credits with a summer course at Harvard Summer School.

Importance of sleep for high school and college students

As difficult as it is to prioritize sleep, the advantages of going to bed early and getting quality sleep every night are very real.

College students who prioritize sleep are likely to see an improvement in their academic performance.

If you are well rested, you will experience less daytime sleepiness and fatigue. You may need less caffeine to stay awake during those long lectures. And you will also find you are more productive, more attentive to detail, and able to concentrate better while studying.

But the connection between sleep and academic performance goes well beyond concentration and attentiveness.

“Sleep is very important for consolidating memories. In any sort of experimental setting, study results show better performance if you learn material and then sleep on it, instead of remaining awake. So there’s lots and lots of evidence now indicating that sleep promotes memory strengthening and memory consolidation,” says Pace-Schott. 

There is also a strong connection between sleep quality and stress.

Students who prioritize sleep are better able to cope with the stress that comes with being an active student. 

“It’s a vicious circle where the more stressed you get, the less you sleep, and the less you sleep, the more stressed you get. And in the long term, that can lead to serious psychiatric problems,” says Pace-Schott.

In the worst case scenario, the combination of lack of sleep and stress can lead to mental health disorders such as depression, general anxiety disorder, and potentially even post-traumatic stress disorder.

But prioritizing sleep can create a positive feedback loop as well. 

Establishing a sleep schedule and adequate sleep duration can improve your ability to cope with stress. Being active and productive will help you get more done throughout the day, which also reduces feelings of stress.

And the less stressed you feel during the day, the better you will sleep at night. 

Tips for getting more sleep as a student

The key to getting a good night’s sleep is establishing healthy sleep habits, also known as sleep hygiene.

The first step is deciding to make sleep a priority. 

Staying ahead of coursework and avoiding distractions and procrastination while you study is key to avoiding the need for late night study sessions. And prioritizing sleep may mean leaving a party early or choosing your social engagements carefully. 

Yet the reward—feeling awake and alert the next morning—will reinforce that positive choice. 

The next step is establishing healthy bedtime and daytime patterns to promote good quality sleep.

Pace-Schott offers the following tips on steps you can take to create healthy sleep hygiene:

• Limit caffeine in close proximity to bed time. College students should also avoid alcohol intake, which disrupts quality sleep.
• Avoid electronic screens (phone, laptop, tablet, desktop) within an hour of bedtime. 
• Engage in daily physical exercise, but avoid intense exercise within two hours of bedtime.
• Establish a sleep schedule. Be as consistent as possible in your bedtime and rise time, and get exposure to morning sunlight.
• Establish a “wind-down” routine prior to bedtime.
• Limit use of bed for daily activities other than sleep (e.g., TV, work, eating)

Of course, college students living in dorms or other communal settings may find their sleep disturbed by circumstances beyond their control: a poor-quality mattress, inability to control the temperature of your bedroom, or noisy roommates, for example. 

But taking these active steps to promote healthy sleep will, barring these other uncontrollable circumstances, help you fall asleep faster, stay asleep, and get a more restorative sleep.

And for students who are still not convinced of the importance of sleep, Pace-Schott says that personal observation is the best way to see the impact of healthy sleep habits. 

“Keep a sleep diary for a week. Pay attention to your sleep in a structured way. And be sure to record how you felt during the day. This can really help you make the link between how you slept the night before and how you feel during the day. It’s amazing how much you will learn about your sleep and its impact on your life.” 

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• About Sleep
• Sleep Facts
• Sleep Resources
• Good sleep is essential for our health and emotional well-being.
• Getting enough sleep and good sleep quality are essential for healthy sleep.
• The amount of sleep you need changes as you age.
• Talk to your healthcare provider if you have problems sleeping.

Getting enough sleep

The daily recommended hours of sleep you need changes as you age.

Sleep Recommended Daily

0–3 months

14–17 hours 1

4–12 months

12–16 hours (including naps) 2

1–2 years

11–14 hours (including naps) 2

3–5 years

10–13 hours (including naps) 2

6–12 years

9–12 hours 2

13–17 years

8–10 hours 2

18–60 years

7 or more hours 3

61–64 years

7–9 hours 1

65 years and older

7–8 hours 1

Health benefits of sleep

Getting enough sleep can help you:

• Get sick less often.
• Stay at a healthy weight.
• Reduce stress and improve your mood.
• Improve your heart health and metabolism.
• Type 2 diabetes.
• Heart disease.
• High blood pressure.
• Lessen the risk of motor vehicle crashes and related injury or death.
• Improve your attention and memory for better perform daily activities.

Better sleep habits can help you get a good night's sleep. Habits that can improve your sleep include:

• Going to bed and getting up at the same time every day.
• Keeping your bedroom quiet, relaxing, and at a cool temperature.
• Turning off electronic devices at least 30 minutes before bedtime.
• Avoiding large meals and alcohol before bedtime.
• Avoiding caffeine in the afternoon or evening.
• Exercising regularly and maintaining a healthy diet.

Sleep quality

Quality sleep means you are getting uninterrupted and refreshing sleep. Getting quality sleep is not just about how many hours you sleep, but how well you sleep.

Signs of poor sleep quality include:

• Trouble falling asleep.
• Repeatedly waking up during the night.
• Feeling sleepy or tired even after getting enough sleep.

Sleep disorders

Some people may have health conditions that prevent them from getting enough quality sleep, no matter how hard they try. These conditions are called sleep disorders.

Common sleep disorders

Common sleep disorders include:

• Restless legs syndrome.
• Narcolepsy.
• Sleep apnea.

Talk to your healthcare provider if you regularly have problems sleeping or notice signs or symptoms of common sleep disorders.

Your provider can run tests, including sleep studies, to tell if you have a sleep disorder.

Keeping a sleep diary

Your provider may have you keep a diary of your sleep habits to better understand what's going on.

Your sleep diary should include when you:

• Wake up during the night.
• Wake up in the morning.
• Drink alcohol or caffeinated drinks.
• Take medications.

What CDC is doing

• High school students .
• CDC's PLACES has local estimates on adults not getting enough sleep.
• Hirshkowitz M, Whiton K, Albert SM, et al. The National Sleep Foundation's sleep time duration recommendations: methodology and results summary. Sleep Health . 2015;1(1):40–43.
• Paruthi S, Brooks LJ, D'Ambrosio C, et al. Recommended amount of sleep for pediatric populations: a consensus statement of the American Academy of Sleep Medicine. J Clin Sleep Med. 2016;12(6):785–786.
• Watson NF, Badr MS, Belenky G, et al. Recommended amount of sleep for a healthy adult: a joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep . 2015;38(6):843–844.

By sharing information and resources, CDC raises awareness about the importance of sleep health and its effect on public health.

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The Effect of Sleep Quality on Students’ Academic Achievement

Rostam jalali.

1 Faculty of Nursing and Midwifery, Kermanshah University of Medical Sciences, Kermanshah, Iran

Habibollah Khazaei

2 Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran

Behnam Khaledi Paveh

Zinab hayrani, lida menati.

Sleep is an inseparable part of human health and life, which is crucial in learning, practice, as well as physical and mental health. It affects the capacity of individual learning, academic performance, and neural-behavioral functions. This study aimed to determine the relationship between sleep quality and students’ academic achievement among students at Kermanshah University of Medical Sciences.

In this cross-sectional study, 102 medical students from different fields, with maximum variation sampling, completed Pittsburgh Sleep Quality Index (PSQI). For data analysis, SPSS 19 was used through which Pearson correlation test, Spearman test, and t -test were employed.

Based on the quality of sleep questionnaire scores, the results indicated no significant difference between students with high grades and those with low grades. However, there were moderate and sometimes severe sleep disturbances in both groups.

The results showed no significant difference between sleep quality and academic achievement. Nevertheless, longitudinal study should be performed to control for confounding factors.

Sleep is an inseparable part of human health and life, and is pivotal to learning and practice as well as physical and mental health. 1 Studies have suggested that insufficient sleep, increased frequency of short-term sleep, and going to sleep late and getting up early affect the learning capacity, academic performance, and neurobehavioral functions. 2 , 3 Previous studies have indicated that the quantity of sleep reported by individuals as delayed or inappropriate sleep, waking up too late, especially at weekends and daytime sleepiness is associated with compromised academic performance in children and adults. 2 Some studies have emphasized the relationship between delayed starting time of classes and academic success. 4 Reduced overnight sleep or altered sleep patterns has been associated with severe drowsiness and failure in academic success. 5 In a study, people who had enough sleep compared to their sleep-deprived individuals used innovative solutions twice as often when confronted with complex mathematical problems. 6 The chance of academic failure was as long as one or more than 1 year in students with inadequate sleep compared to those with proper sleep. 7 People who sleep less and sleep during the day are more prone to vehicle and work accidents. 8 In some studies, sleep efficiency has been considered as essential for recovery, cognitive processing, and memory integration. 9 On the other hand, lack of sleep has been associated with emotional instability and impaired concentration. 10 In this regard, students are particularly at risk of developing sleep disorders and development of the disorder among them has a negative effect on their academic performance across different grades, 11 – 13 However, there is no consensus in this case and not all studies state that sleep disorders yield a negative effect on academic performance. Eliasson (2010) believes that the time it takes to fall asleep and waking up affect academic performance more than duration of sleep does. 14 Sweileh and colleagues (2011) also believe that there is no relationship between sleep quality and academic success. 15 Similarly, it is claimed there is no relationship between the night sleep before the exam and test scores either. 16

In another study, the author believes stress from lack of sleep causes poor school performance. 17 On the other hand, in a systematic review, the authors could not establish a cause and effect relationship between sleep quality and academic performance. 2 In their meta-analysis study, Dewald and colleagues (2010) emphasized that because of the diversity of the methodology of studies, it is impossible to definitely derive a relationship between sleep quality and academic performance, and thus more longitudinal intervention studies are warranted. 1 According to different conclusions in this respect, the researchers decided to determine the relationship between sleep quality and academic performance among students at Kermanshah University of Medical Sciences.

In this cross-sectional study, through maximum variation sampling, the first three students with highest scores and three last students with lowest scores were selected, and the Pittsburgh Sleep Quality Index (PSQI) was completed for them.

The study population consisted of students of Kermanshah University of Medical Sciences. The samples were also students at each school with the highest GPA (first three high scores) and the lowest GPA (last three lowest scores). The sampling was purposeful sampling with maximum variation. The sample covered a number of disciplines in the third semester and above ( Figures 1 & 2 ). After determining the target students, the questionnaire was given to them and then returned to the researcher after completion.

Abundant distribution of students by field of study.

Frequency distribution of students by semester.

The data collection instruments were demographic form (including age, gender, place of residence, grade, rank in the class, discipline) and Pittsburgh Sleep Quality Index (PSQI). PSQI is a self-report questionnaire which examines the quality of sleep. It has 18 questions which are classified into seven components: the first component is the subjective sleep quality which is determined with Question 9. The second component is related to delays in falling asleep, where the score is calculated by two questions, the mean score of Question 2 and part of Question 5. The third component deals with sleep duration and is determined by Question 4. The fourth component is related to the efficiency and effectiveness of sleeping in patients. Its score is calculated via dividing the total hours of sleep by total hours in the bed multiplied by 100. Then, the fifth component deals with sleep disorders and is achieved by calculating the mean value of Question 5. The sixth component is related to hypnotic drugs and is determined based on Question 6. Finally, the seventh component captures inadequate performance throughout the day and is determined by two questions (mean scores of Questions 7 and 8). Each question is rated between 0 and 3 points where maximum score for each component is 3. The total scores range of the seven components making up the total score range from 0 to 21. Higher scores represent a lower sleep quality, where a score above 6 indicates poor sleep quality. The reliability and validity of this inventory have also been approved in Iran, where the Cronbach’s alpha coefficient of the questionnaire was 0.78 to 0.82. 18 In another study, Cronbach’s alpha for the Persian version was 0.77. In cut-off point 5, the sensitivity and specificity were 94% and 72%, and in cut-off point 6, they were 85% and 84%, respectively. 19

After collecting the questionnaires and introducing students’ demographic data to a computer using SPSS version 16, the relationship between sleep quality scores and grade point average (GPA high and low) was calculated.

The results indicated that 34 cases (33.3%) of the subjects were male. The mean age of the sample 23.10 ± 3.25, where the mean age for females was 22.46± 2.44 and for males was 24.38± 4.19. The participants in the study came from various disciplines including laboratory science, medicine, pharmacology, emergency medicine, obstetrics, radiology, operating room, health technology, and nursing.

Most students lived in dormitories (50%) and 46.1% at home, with 3.9% living in rental houses. The students' educational level ranged between the third semester and twelfth semester.

Among those participating in the study, 67 patients (65.7%) consumed coffee, 90 cases (88.2%) used tea, and 1 (1%) took a drug.

For comparing the mean scores of students and the component of sleep, Spearman test (non-normal data) was employed, where a significant correlation was observed between GPA and hours taking to fall asleep ( Table 1 ).

The Relationship Between Sleep Components and GPA in KUMS Students

Similarly, there was a relationship between sleep components and tea, coffee, hypnotic drugs, and drug ( Table 2 ).

The Relationship Between Sleep Components and Type of Drink or Drug in KUMS Students Kermanshah

On the other hand, independent t -test between Pittsburgh scores in the two groups did not show any significant differences. Nevertheless, impaired sleep quality was moderate to severe in both groups ( Table 3 ).

The Difference Between the Mean Pittsburg Scores in Two Groups (Students with High and Low GPA)

The results indicated that impaired sleep quality between the two groups was not statistically significant. Although the relationship between sleeping and academic success has been introduced in medical literature since a long time, there still no definitive answer in this case. In a meta-analysis study conducted to examine the impact of sleep quality, sleep duration, and sleepiness on adolescents’ academic performance, although all three variables were related to academic achievement (positive relationship between sleep quality and duration of sleep and negative association with sleepiness), this relationship was very trivial. 1

On the other hand, another systematic review study of descriptive studies concluded that sleep disturbance adversely affects different areas such as general health, social status, and academic performance. However, longitudinal studies are required for a more accurate examination. 20 , 21 In an another systematic review of other authors, the authors concluded that under-sleeping would have an impact on learning of some students, and could have a detrimental effect on academic achievement. 22 Further, another review study also suggests a conclusive recommendation which has to be done to modify sleep so that it can be used for academic success. 23

The present study was conducted to explore whether sleep disorder can influence academic achievement or not. Accordingly, a specific sample of accomplished or unachieved students were selected to compare the quality and quantity of sleep. However, no significant difference was between the two groups. Other studies have reached similar conclusions.

Sweileh and his colleagues in a study on 400 Palestinian students concluded that academic achievement was not correlated with sleep quality. 15 In another study on 189 medical students in Pakistan, there was no significant association between lack of sleep and test scores. 16 In this regard, there is a possibility of sleep disorder in students, and this possibility has been expressed for the lack of academic achievement, but it has not been clearly explained. 11 In another study, sleepiness during the day (not the quality and quantity of sleep) was identified as an independent predictor of academic success. 5 In a similar study again the time it takes to fall sleep and the wake-up time (not the total amount of sleep) were associated with academic success, 14 where the total amount of sleep in adolescents with a dynamic mind was not related to their academic achievement. 24 In contrast to such studies that emphasize lack of association or low association, there are other studies that have observed an inverse relationship between sleep disturbance and academic achievement. In a study on 491 first-, second-, and third-year medical students, there was a correlation between academic performance and the amount of nighttime sleep as well as daytime sleepiness. 25 In a similar study on medical students, lack of sleep at night, late going to bed, and daytime sleepiness had a negative effect on the academic performance of the students. 26 Notably, sleep disturbances are likely to yield a negative impact on academic performance, thereby causing a vicious cycle. 25 , 27 Taken together, the studies suggest that most studies have mentioned poor quality sleep among the majority of students. 3 , 26 , 27 Accordingly, concluding the relationship between common sleep disturbance and academic performance should be done with caution. The reason is that academic success can be affected by different factors including the level of family income, the evolutionary process, intake of supplements and vitamins, family size, social media dependency, addiction to social networks, and social issues. In studies these extraneous factors are not under control, thus emphasizing the fact that the presence or absence of correlation between sleep quality and academic performance should be done with caution and using longitudinal studies.

Limitations

The main limitation of this study was the small sample size, but a specific sampling method was chosen to overcome this shortcoming. Another limitation of the study was not controlling for confounding factors in the study. Based on the results of this study and similar studies, further research should be conducted with a better design.

The results indicated no significant difference between sleep quality in achieved and unachieved academic performance. Nevertheless, to conclude with more certainty, longitudinal studies should be performed to control confounding factors.

Acknowledgments

The authors of this article appreciate the collaborations of the Sleep Disorders Research Center.

Funding Statement

Funding for this research was provided by the Kermanshah University of Medical Sciences, Sleep Disorders Research Center (93026).

Data Sharing Statement

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Ethics Approval and Consent to Participate

Informed consent obtained from all participants in the study and this study conducted by the Sleep Disorders Research Center. Identity letter obtained from deputy of research and technology to collecting data. Ethics approval was received from the ethics committee of deputy of research and technology – Kermanshah University of Medical Sciences, number 93026 on 6 April 2013.

The authors declare that they have no conflict of interest.

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The Importance of Sleep by Kealey

Kealeyof Logan 's entry into Varsity Tutor's July 2017 scholarship contest

The Importance of Sleep by Kealey - July 2017 Scholarship Essay

Sleep is one of the most important aspects of our lives. For many, sleep is too often undervalued. But when all's said and done, we should place sleep as a higher priority in our lives because it enhances our physical and cognitive performance, improves our memory, and supports survival mechanisms. Sleep provides cognitive and physical health benefits that allow the human body to function more properly. I personally perform better in all aspects of life if I receive adequate amounts of sleep. Because of this, I strive to be in bed by my set bedtime (no later than 10:30 pm). There are instances, specifically on the weekend that I stay up later. In contrast, my father does not get enough sleep. During my teenage years, he would consistently go to bed around 11 pm or midnight and wake up at either 3:00 or 4:00 am. The reality of the need for sleep finally sunk in when my dad was diagnosed with Pseudotumor cerebri, or swelling of the optic nerve. Other health problems escalated as an after effect. Although there are no known causes of this condition, the doctors suggested that inadequate amounts of sleep may have been a contributing factor. In findings reported by the National Institution of Health,sleep is necessary to heal and repair the body’s immune functions, regulate a healthy balance of hormones, and also aids in growth and development. Like my father, sometimes the suffering presents itself in extremities. But more often than not, little things such as the common cold or flu affect those that don’t get enough sleep more. Because sleep is individualized, a person must ensure they get adequate amounts of sleep for proper physical functioning on a daily basis. Not only does sleep affect our physical abilities, it can enhance our overall mental abilities. In general, humans function better when they get enough sleep. Dr. Ferraro and Dr. Genarro, two Italian sleep psychologists, suggest a direct correlation indicating that performance ability declines as the number of hours of sleep declines. During sleep the brain builds and strengthens neurological pathways. When not enough sleep occurs, a person increases their risk of developing mental illnesses such as depression. Thus, this evidence provides support for doctors and therapists who suggest sleep as a remedy, both to cure physical and cognitive illnesses. Sleep also affects our memory. Being able to remember, retain, and recall are the three “Rs” to memory. The human memory relies on sleep for the enhancement of these. Dr. Jan Born, and Dr. Ines Wilhelm, two German psychology professors, recently conducted a study to find the relationship between sleep and memory. Their research indicates that sleep helps convert implicit knowledge or patterns, into explicit knowledge that is retained in the brain. Memory consolidation cannot happen correctly without sleep. Born and Wilhelm also found that sleep improves long-term memory. They suggest that sleep could be the process in which newly encoded memory representations are redistributed to other neuron networks serving as long-term storage. When I practiced for piano competitions in high school and attempted to memorize a song, I often played it right before bed. The next day, I could recall the music better compared to practicing it in the early afternoon. Thus, sleep becomes a beneficiary factor for memory. Sleep is not an independent variable. In fact, although sleep is important, there are many other things that are necessary to having a well-balanced life. Culture, family, work, social life, and values all determine one’s way of living. Despite the situations that make up a person’s life, sleep deserves greater prioritization. Dr. Michael Colgan, a world-wide renowned research scientist relates, “Sleep could be considered more important than food in maintaining physical and cognitive health if water supply is sufficient.” Sleep acts as as a survival tool, when not put to use, it can cause serious work-related and life-threatening crises. In 2005, The National Sleep Foundation found about 60% of all drivers have driven drowsy, furthermore 100,000 car accidents are sleep related. This included 1550 deaths and 71,000 injuries. This lack of sleep is a weapon: the sleep deficient driver becomes the offender, and other drivers on the road become the victims. Detecting drowsy driving tends to be more difficult to detect than things such as seat belt usage or driving under the influence. But, sleep deprivation and fatigue make lapses of attention more likely to occur. Sleep is a major factor that potentially saves lives. Even with the productivity of our society, Americans need to place a greater importance on sleep. Sleep is beneficial to maintaining and improving our cognitive and physical performances, memory functions, and acts a survival mechanism. As Russell Foster put it “Sleep is the golden chain that ties all aspects of health [and life] together.” If we placed sleep as a greater importance in our society, there would be less accidents, injuries, illnesses, and overall greater happiness levels. Take the initiative and start today to get enough sleep; crawl into your pajamas, and snuggle on into your bed for a full night's sleep.

Essay on Importance of Sleep

Students are often asked to write an essay on Importance of Sleep in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Importance of Sleep

Understanding sleep.

Sleep is a crucial part of our lives. It helps us rest, rejuvenate, and prepare for the next day. Without sleep, our bodies and minds cannot function properly.

Why is Sleep Important?

Sleep contributes to our overall health. It allows our brain to process information and memories. It also gives our body time to repair and grow.

Effects of Lack of Sleep

Lack of sleep can lead to health issues like heart disease and obesity. It also affects our mood, making us feel irritable and stressed.

So, quality sleep is essential for our well-being. Make sleep a priority to stay healthy and happy.

250 Words Essay on Importance of Sleep

The necessity of sleep.

Sleep, often overlooked in our fast-paced society, is a fundamental aspect of human health and well-being. Its importance extends beyond merely banishing under-eye circles or boosting mood; it is an essential part of our biological function.

Role in Physical Health

Sleep plays a significant role in the body’s healing and repair processes, particularly for the heart and blood vessels. Chronic sleep deficiency is linked to heart disease, kidney disease, high blood pressure, diabetes, and stroke. Furthermore, it aids in maintaining a healthy balance of hormones that regulate feelings of hunger and satiety, thereby indirectly influencing our body weight and food choices.

Cognitive Function and Emotional Well-being

Sleep is vital for various aspects of brain function. This includes cognition, concentration, productivity, and performance. During sleep, your brain forms new pathways to help you learn and remember information. A good night’s sleep improves problem-solving skills and enhances memory. Lack of sleep impairs these functions, leading to decreased productivity and increased mistakes.

The Impact on Mental Health

Sleep deficiency has been linked to an increased risk of developing mental health disorders, including depression, anxiety, and mood swings. Sleep helps reset our emotional brain circuits, allowing us to manage daily stress and adapt to change.

In conclusion, sleep is not a luxury, but a necessity. It’s a vital part of our lives that impacts our physical health, cognitive function, emotional well-being, and overall quality of life. Recognizing the importance of sleep and making necessary adjustments to prioritize it is a crucial step towards improved health and productivity.

500 Words Essay on Importance of Sleep

The importance of sleep: an underrated aspect of health.

Sleep, often overlooked, is a crucial aspect of our overall health and well-being. In our fast-paced society, sleep is frequently sacrificed for more seemingly productive activities, however, this neglect can have serious health consequences.

The Science of Sleep

Sleep is not merely a passive state where the body is at rest. It is a complex physiological process where essential activities occur. During sleep, the body undergoes repair and rejuvenation, and the brain processes and integrates information gathered throughout the day. Sleep is divided into two distinct types: Rapid Eye Movement (REM) sleep and Non-Rapid Eye Movement (NREM) sleep. Each stage has specific functions, with NREM sleep primarily involved in physical restoration and REM sleep associated with memory consolidation and brain development.

The Health Implications of Sleep Deprivation

Chronic sleep deprivation can lead to a host of health problems. Physically, it can increase the risk of conditions such as obesity, diabetes, and cardiovascular disease. It weakens the immune system, making one more susceptible to infections. Neurologically, lack of sleep can impair cognition, memory, and mood. Studies have shown that sleep deprivation can lead to decreased concentration, memory lapses, loss of creativity, and mood swings. Furthermore, chronic sleep deprivation has been linked to mental health disorders such as depression and anxiety.

Sleep and Academic Performance

For college students, sleep is especially important. Numerous studies have demonstrated a correlation between sleep and academic performance. Adequate sleep can enhance learning and memory, improve concentration, and boost creativity, all of which are crucial for academic success. Conversely, sleep deprivation can impede these cognitive functions, leading to decreased academic performance.

Improving Sleep Quality

Given the importance of sleep, it is essential to prioritize it and adopt good sleep hygiene practices. These include maintaining a regular sleep schedule, creating a sleep-friendly environment, avoiding stimulating activities before bedtime, and addressing any underlying sleep disorders.

In conclusion, sleep is a crucial aspect of health that is often undervalued. The implications of sleep deprivation are far-reaching, affecting physical health, mental health, and cognitive functions. As college students, it is essential to prioritize sleep to maintain overall health and optimize academic performance. By understanding the importance of sleep and adopting good sleep hygiene practices, we can reap the benefits of this vital physiological process.

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The Importance of Sleep

Constantly tired, grey faces with red, puffy eyes, hands holding cups loaded with caffeine… Lack of sleep seems to be a plague among the modern youth. We live in a constant rush, our schedules are overflowing with various tasks and responsibilities, and rest usually ends up as the lowest priority on our lists. People tend to underestimate the importance of good-quality sleep, without realising the consequences. Moreover, many of us don’t know what “quality sleep” even means – how long we should sleep, how to make sure we actually get enough rest and how to take care of appropriate sleep hygiene. This article will be your first step to finally getting a good night’s sleep.

First things first – do you know why sleep is so important? We all know that sleep is the time when our body and brain regenerate. Let's get down to a bit of science: it is the time when your heart and blood vessels heal and repair, protecting you from heart and kidney diseases, strokes and low blood pressure. Sleep is also an important factor for lowering the risk of diabetes, as it affects how your body reacts to insulin (the hormone that controls your blood sugar level).

If you still don’t feel convinced, good sleep can help you maintain appropriate body weight! Have you noticed that when you are sleepy, you are also more prone to reaching for comfort foods instead of healthy, nutritious meals?  Night time is when your body produces hormones, including ghrelin and leptin – hormones responsible for feeling hungry and full. What this actually means is that sleep deprivation lowers your metabolism, making you more likely to gain weight.

Good sleep is important for your mind as well. Obviously, feeling well-rested affects your mood, response time, and efficiency at work. Studies show that sleep has a crucial impact on activity in some parts of the brain. If you're tired, you may have trouble making decisions, solving problems, controlling your emotions and behaviour, and coping with change.

Now that you know why you should always get enough sleep, it’s time to find out how. Have you ever wondered how much sleep is “enough”? Or if there is such a thing as too much sleep? For an adult, the appropriate amount is between 7 and 9 hours. This means that sleeping over 9 hours per day can actually be bad for you. Oversleeping has similar effects to sleep deprivation: over time it can also lead to diabetes, obesity, and heart disease. More common effects of sleeping too much are headaches, lack of energy or depression. Sounds familiar? Remember that anything in excess is bad.

It’s not only how much sleep you get that’s important – if the quality of sleep is not right, you will not get its full benefits. There are a few tricks that can help you get as much rest as possible. You need to take care of a proper sleep hygiene. Firstly, remember that your bed should be reserved for sleep only – if you have a habit of working or eating in bed you should try to move it to somewhere else. Studies prove that separating workspace and sleeping space can help you fall asleep faster and sleep better throughout the night. And there’s bad news for those addicted to phones – the blue light from the screen disrupts natural sleep patterns by affecting melatonin (sleep hormone) levels. Does avoiding touching your phone and laptop for two hours before sleep sound impossible? At least switch all of your devices to night shift mode – it gives a yellow tint to your display, minimising the negative effect on your hormones. If your device doesn’t have a built-in night mode, you can try Twiligh t (for Android) or f.lux (for Windows).

If you have trouble falling asleep, you should try going to bed and waking up around the same time each day. It might be challenging, especially during weekends, but once you establish a routine, waking up early during the week becomes much easier.  Humans are creatures of habit, so having a nice bedtime routine – a time for you to unwind, relax, and get ready for bed - is the first step to good quality sleep. You can pick out an outfit and pack your bag for the following day, have a nice, warm bath, listen to some music, set time to read a book… try out what works best for you and stick to it!

Maybe it sounds like a lot of restrictions, hard to keep up with when you have a fully packed schedule and tight deadlines –  but still, sleep should be a priority. You’ll be much more efficient finishing everything in your crowded schedule with a rested brain, good energy, and positive attitude – not to mention that after a full night of sleep, those busy days will also feel better. Don’t you think it is worth sacrificing one thing in order to get proper rest? In the long run, it will bring you much more benefit and help you manage your time and tasks better. Good luck – and sleep well!

P.S. You can read up more about the science of sleep here .

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Essay: The Importance of Sleep

RockeyOP 1 / -   Dec 3, 2013   #1 Must be 2 pages but any thing would be greatly appreciated. The topic of the essay should be the Importance of sleep.

kelibzon - / 1   Dec 7, 2013   #3 Introduction A recent survey revealed that a large number of people sleep less than six hours each night, and that 75 percent of people encounter sleep difficulties a few nights a week. While a short-lived insomnia should not be of much concern, chronic sleep loss can lead to a myriad health problems including high blood pressure, weight gain, low immune system and much more. This essay explains the different ways in which sleep is important. The Importance of Sleep Mental and Emotional Well being Sleep promotes a healthy brain functioning and emotional well being. When one sleeps, the brain is able to commit new information to the memory via a process known as memory consolidation. Studies show that individuals who slept after learning a new task performed well in tests than those who did not. Children and teens that are sleep-deficient are likely to encounter problems when it comes to getting along with their peers. They may feel impulsive and angry, feel sad, have mood swings, lack motivation or feel depressed (NIH, 2012). Mood Enhancement, Metabolism and Weight Control Sleep determines an individual's mood. Sleep loss may lead to irritability, lack of concentration, impatience, and moodiness. Inadequate sleep can also make one fatigued and unable to handle their normal tasks. This therefore means that sleep can help to boost one's mood, improve their concentration and put them in the right frame of mind to perform the normal tasks (Harvard Health Publications, 2006). Sleep helps in metabolism and weight control. Prolonged sleep deprivation can result to weight gain as it affects the processing and storage of carbohydrates in the body besides altering the hormone levels that affect one's appetite (Harvard Health Publications, 2006). Safety and Alertness Sleep enhances safety and alertness when performing different tasks. Sleep debt increases the tendency of falling asleep or feeling drowsy at daytime. Such lapses may result to falls and other mistakes such as air traffic mishaps, medical errors, and road accidents. Studies indicate that sleep deficiency weakens one's ability to drive as much as, or even more than drinking does. Precisely, driver sleepiness is responsible for about 100,000 motor vehicle accidents every year, which results in around 1500 deaths (NIH, 2012). Improves Cardiovascular Health Sleep improves cardiovascular health and reduces the risks of suffering from heart related conditions such as hypertension, irregular heartbeat and many more (Harvard Health Publications, 2006). Hormonal Balance Sleep creates a healthy balance of those hormones that make one to feel full (leptin) or hungry (ghrelin). Inadequate sleep increases the level of ghlerin and lowers the level of leptin. This makes one to feel hungrier than when they are well-rest. Sleep enhances good growth and development. For instance, deep sleep will trigger the body to release a hormone responsible for the promotion of normal growth in teens and children. Besides, this hormone boosts the muscle mass and helps in the repair of tissues and cells in teens, children and adults. Sleep plays a critical role in fertility and puberty too (NIH, 2012). Boosts the Immune System Moreover, sleeping improves the immune system, which is the body's natural defense against ailments. Thus, sleep deprivation can alter the immune function and make one susceptible to a number of diseases. According to medical study, newborns should sleep for 16-18 hours each day; preschool- and school-aged children should sleep for 11-12 hours and 10 hours per day respectively. Teens should spend 9-10 hours a day sleeping and adults should sleep for 7 to 8 hours every day (NIH, 2012). Conclusion Sleep enhances the mental and emotional well being of children, teens and grownups. Sleep controls metabolism and weight; lack of sleep can cause weight gain. Adequate sleep boosts the right mood for productivity and improves safety when performing daily tasks. Besides, sound sleep promotes hormonal balance and boosts the immune system. References Harvard Health Publications (2006). Importance of Sleep: Six Reasons not to Skrimp on Sleep. Harvard Medical School, Harvard University NIH (2012). Explore Sleep Deprivation and Deficiency: Why is Sleep Important? Department of Health and Human Services: USA Gov. Hope this helps. If you need more academic help, please let me know via kevslibama (at) gmail dot com Kelibzon